INFO: task syz.4.166:6901 blocked for more than 143 seconds. Not tainted 6.11.0-rc7-syzkaller-00021-g7c6a3a65ace7 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.166 state:D stack:24672 pid:6901 tgid:6899 ppid:6234 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 percpu_rwsem_wait+0x3c2/0x450 kernel/locking/percpu-rwsem.c:162 __percpu_down_read+0xee/0x130 kernel/locking/percpu-rwsem.c:177 percpu_down_read include/linux/percpu-rwsem.h:65 [inline] __sb_start_write include/linux/fs.h:1676 [inline] sb_start_write+0x184/0x1c0 include/linux/fs.h:1812 mnt_want_write+0x3f/0x90 fs/namespace.c:515 filename_create+0x184/0x540 fs/namei.c:3972 do_mkdirat+0xbd/0x3a0 fs/namei.c:4225 __do_sys_mkdirat fs/namei.c:4248 [inline] __se_sys_mkdirat fs/namei.c:4246 [inline] __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4246 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9afb97c797 RSP: 002b:00007f9afc808e68 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f9afc808ef0 RCX: 00007f9afb97c797 RDX: 00000000000001ff RSI: 0000000020000100 RDI: 00000000ffffff9c RBP: 0000000020000000 R08: 0000000020000000 R09: 0000000000000000 R10: 0000000020000000 R11: 0000000000000246 R12: 0000000020000100 R13: 00007f9afc808eb0 R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: 3 locks held by kworker/u8:0/11: #0: ffff88802f627948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff88802f627948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90000107d00 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90000107d00 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffff8880b882a718 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x744/0xeb0 kernel/time/timer.c:1164 1 lock held by khungtaskd/30: #0: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #0: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6626 3 locks held by kworker/1:1/52: 3 locks held by kworker/u8:5/991: 2 locks held by kworker/u8:9/2533: #0: ffff88801a889148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff88801a889148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90008adfd00 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90008adfd00 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 2 locks held by getty/4980: #0: ffff8880235580a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000311b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6ac/0x1e00 drivers/tty/n_tty.c:2211 1 lock held by syz.4.166/6901: #0: ffff888032fbc420 (sb_writers#13){++++}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515 1 lock held by syz-executor/8834: #0: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644 1 lock held by syz-executor/8948: #0: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644 8 locks held by syz-executor/9097: #0: ffff888034b0a420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2882 [inline] #0: ffff888034b0a420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x227/0xc90 fs/read_write.c:586 #1: ffff88805bda6088 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1eb/0x500 fs/kernfs/file.c:325 #2: ffff888027dbec38 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20f/0x500 fs/kernfs/file.c:326 #3: ffffffff8f314108 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216 #4: ffff88805ce310e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #4: ffff88805ce310e8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1094 [inline] #4: ffff88805ce310e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xce/0x7c0 drivers/base/dd.c:1292 #5: ffff888028036250 (&devlink->lock_key#27){+.+.}-{3:3}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1672 #6: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: nsim_destroy+0x71/0x5c0 drivers/net/netdevsim/netdev.c:773 #7: ffffffff8e73d6f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:296 [inline] #7: ffffffff8e73d6f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:958 3 locks held by dhcpcd-run-hook/9218: #0: ffff8880b893e998 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:560 #1: ffff88807baab118 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:122 [inline] #1: ffff88807baab118 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:636 [inline] #1: ffff88807baab118 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1672 [inline] #1: ffff88807baab118 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x29a/0x1f30 kernel/fork.c:1721 #2: ffff88806f43fcd8 (ptlock_ptr(ptdesc)#2){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline] #2: ffff88806f43fcd8 (ptlock_ptr(ptdesc)#2){+.+.}-{2:2}, at: __pte_offset_map_lock+0x1ba/0x300 mm/pgtable-generic.c:375 1 lock held by dhcpcd-run-hook/9227: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-rc7-syzkaller-00021-g7c6a3a65ace7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xff4/0x1040 kernel/hung_task.c:379 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 51 Comm: kworker/u8:3 Not tainted 6.11.0-rc7-syzkaller-00021-g7c6a3a65ace7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:task_wait_context kernel/locking/lockdep.c:4712 [inline] RIP: 0010:check_wait_context kernel/locking/lockdep.c:4793 [inline] RIP: 0010:__lock_acquire+0x7e2/0x2040 kernel/locking/lockdep.c:5092 Code: 03 48 8b 34 24 48 ba 00 00 00 00 00 fc ff df e9 65 ff ff ff 65 8b 05 d9 ac 92 7e b3 02 85 c0 75 21 48 8b 44 24 58 0f b6 04 10 <84> c0 0f 85 66 14 00 00 48 8b 44 24 18 83 38 00 0f 94 c3 00 db 80 RSP: 0018:ffffc90000bb78f0 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 0000000000060602 RCX: 0000000000000001 RDX: dffffc0000000000 RSI: ffff88801af746e0 RDI: 000000000000000a RBP: 00000000ffffffff R08: ffffffff93fa6847 R09: 1ffffffff27f4d08 R10: dffffc0000000000 R11: fffffbfff27f4d09 R12: 0000000000000000 R13: ffff88801af746d8 R14: 1ffff110035ee8ea R15: ffff88801af74750 FS: 0000000000000000(0000) GS:ffff8880b8900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0c083975a0 CR3: 000000000e534000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759 rcu_lock_acquire include/linux/rcupdate.h:326 [inline] rcu_read_lock include/linux/rcupdate.h:838 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xec/0x610 net/batman-adv/network-coding.c:719 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd10 kernel/workqueue.c:3389 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244